Until now, it is not possible to implement first person games in which a user can act and move in a virtual environment like being in reality because of two main problems. First, it was not possible to determine the viewing direction of an object accurately enough. Second, localization of objects cannot be performed precisely in a manner of a couple of centimeters with known systems. Additionally, processing times have to be at a minimum in order to convey a real interaction with the system. Third, current approaches apply more or less restricted hardware setups like, for example, the so-called 2D Cyber Walk platform from treadmill or simulators known from aeronautic or automotive.
This Cyber Walk platform is very inflexible as ground controls for the floor and massive electronic devices to the head have to be installed. Furthermore, interaction with other users would necessitate such a setup for any person that is contributing.